Door lock mechanism



April 3, 1251 E. l. sTULPlN ET AL 2,547,546

DOOR LOCK MECHANISM File'd Aug. 3, 1949 atented Apr. 3, 1951 DOOR LDCK MECHANISM Edward I. Stulpin and Walter R. Hajdyla, Detroit, Mich.

Application August 3, 1949, Serial No. 108,377

2 Claims. (Cl. 292-166) This invention relates to an improved door lock mechanism and particularly to lock mechanism of the latch bolt type.

An object is to provide lock mechanism having a spring projected reciprocating latch bolt with simple plunger actuated means coupled therewith to retract the bolt counter to the action of a spring and with a simple lock pin to secure the plunger actuated means against movement so as to prevent release of the bolt.

A further object is to provide simple, inexpensive, rugged, easily installed and easily operable lock mechanism of the latch bolt type wherein there is a latch bolt hold normally projected by a spring and wherein there is a plunger `coupled with the latch bolt through a rockably supported bellcrank lever responsive to the depression of the plunger to be rocked thereby to actuate the latch bolt counter its spring, and wherein there is further provided a lock pin mounted for reciprocation and adapted in one position of reciprocation to engage one arm `of the lever and prevent rocking movement thereof and adapted in another position of reciprocation to release the lever for rocking movement to actuate the bolt.

More particularly, an object is to provide lock mechanism wherein a latch bolt is reciprocably supported within a housing to be spring projected and a plunger is supported within a housing Vto be manually depressed and a bellcrank lever is swingably supported intermediate the plunger and the latch bolt, and so, disposed as to be swung by depression of the plunger and so coupled with the latch bolt that upon depression of the plunger the latch bolt is retracted by the bell-crank lever; all characterized by the provision of a lock pin reciprocably mounted adjacent the bellcrank lever and having a part adapted, in one position of reciprocation of the pin, to be brought underneath that arm of the bellcrank which is in direct contact with the plunger to prevent rocking of the bellcrank lever. In the other position of reciprocation of the lock pin the bellcrank lever is released so as to be freely rocked by the plunger.

Other objects, advantages, and meritoriousfeatures will more fully appear from the following description, claims and accompanying drawing, wherein:

Fig. 1 is an elevation of a fragment of the edge of a door provided with our improved lock mechanism showing the same in elevation;

Fig. 2 is a sectional view taken on the line 2-2 of Fig. l showing a fragment of a door provided with our improved lock mechanism and showing the lock mechanism partly broken away and partly in section;

Fig. 3 is a cross-sectional view taken on the line 3 3 of Fig. 2;

Fig. 4 is a cross-sectional view partly in elevation taken on the line 4-4 of Fig. 2;

Fig. 5 is a fragmentary section through a modied form of construction; and

Fig. Gis a sectional view on line G-S of Fig. 5.

This lock mechanism is particularly designed for use on communicating doors between rooms in a dwelling, as for example, a bathroom door. The lock mechanism is simple. It is made up of few parts. It can be easily installed. The latch bolt is easily retracted by a manually depressible plunger or button. Mechanism can be releasably locked from one side against actuation from the opposite side.

In the drawing let lI8 indicate a door and l2 a door jamb member. The door jamb is provided with a striker plate ifi and a door stop The door carries the lock mechanism. This lock mechanism comprises a latch bolt it supported within a housing i for reciprocation. The bolt is. held normally projected by a spring 22. A stop pin 23 is provided. The housing is cut-away at the rear and the bolt itself is slottedtransversely on opposite sides at the rear to receive the end of a rockably supported bellcranklever 2G. 28 indicates a retaining plate to secure the housing 2l) in place.

The door isV provided on opposite sides with latch bolt actuating mechanism in the form of a plunger 3B provided at one end with a thumb cap 33. This plunger is reciprocably supported within part of a housing 32 as shown in Fig. 2. Within this housing 32 the bellcrank lever 26 is pivoted upon a pivot ypin 34, as shown in Fig. 2. One arm of this bellcrank lever has an end portion 35 which is received within the slot 24 of the latch bolt. The other arm of the bellcrank lever stands underneath the plunger pin 3i) so as to be depressed thereby. It is apparent that depression of the plunger 30 will serve to swing the bellcrank lever to retract the latch bolt counter its spring 22.

There is also provided on each side of the door a handle portion 38 which may be secured to the door at one end as at 4l! in any suitable manner. The opposite end of this handle member terminatos in a barrel 42 which serves as a housing surrounding the plunger, as shown in Figs. 1 and 2. The casing 32 which carries the actuating mechanism may be sec`ured to the door by screws or pins 4t, as shown in Fig. 4. This casing 32 may be provided with flange parts 46 which are receivable within out-outs in the body of the door, as shown in Fig. 3.

While only one assembly is shown complete in Fig. 2, it is apparent that two assemblies would be provided as illustrated in Fig. 1 and broken away portions thereof are shown in Fig. 2.

In the figures of the drawing there is shown on one side of the door only a lock pin which is adapted to be actuated to secure the mechanism against operation of the latch bolt. This lock pin is indicated as 48. It is supported for reciprocation within the casing 32. It extends parallel to the latch bolt'and Vsubstantially parallel to ithat arm of the bellcrank 'which lies ydirectly underneath the plunger 30. Such pin 48 is cut-away on one side as at 50 providing a flatted portion ter-- minating in end shoulders. The bellcranklever which is engaged by the plunger 30 isnotcherlv as at 52 to seat upon one of these end shoulders when the lock pin 48 is projected to the position shown in solid line in Fig. 2. It is apparent that when the lock pin is projected 'to 'its opposite position of reciprocation that the bellcrank .lever will be released to swinging movement, but when thelock pin is located as shown in Figs. 2 and 4 the bellcrank leveris held against swinging movement in response to urging of the plunger 30. A friction ring 49of rubber or the like encircles the pin as shown in Fig. 2 being seated in a ring groove in the pin to hold the pin releasably at adjusted positions.

Figs. 5 and 6 illustrate a. modification in which the construction is such that manual actuation of the plunger 38 serves rst to withdraw the lock pin 48 and thereafter to swing the bellcrank 2S to withdraw the latch bolt. This result is accomplished by providing a modiedform of plunger. Such plunger is cut-away or grooved on one side at its inner end as at 52 providing a shoulder 54 spaced from the bellcran'k lever 26 as shown in Fig. 6, so as to permit slight inward movement of the `plunger before the bellcrank lever is picked up. The plunger has an end eX- tension which overlaps the bellcrank lever and which is itself beveled as at 56 to engage the shoulder 58 of the lock pin 48, as shown in Fig. 5, to retract the lock pin before the shoulder 54 of the plunger engages the bellcrank lever to swing it.

What we claim is:

1. Lock mechanism comprising, in combination, a latch bolt, a spring acting upon the bolt holding it normally projected, a plunger, a swingably sup-ported bellcrank lever having one arm coupled with the bolt andthe other arm disposed in proximity to the plunger to be actuated thereby to swing the lever to actuate the bolt counter to the action of said 'spring and a lock pin sup- 'adapted in the opposite position of reciprocation to-.release-,the lever for swingable movement, said plunger so shaped as to provide a part which 'initial-ly engages the lock pin to retract it before the lplunger engages the bellcrank lever.

2. VLock y,mechanism comprising, in combination, a`la`tchfbolt supported within a housing for-"reciprocation, a spring holding the latch bolt normally projected, a plunger supported within a housing ,for reciprocation, said plunger having a laterally recessed -atted face vextending from the inner end lengthwise thereof and terminating in a shoulder, a beveled surface on the inner endof the plunger, a bellcrank lever swingably supported having one arm coupled with the latch bolt and having its other arm disposed adjacent to the atted surface of the plunger and Substantially underneath the shoulder, a lock pin mounted for reciprocation substantially parallel to the latch bolt, said pin having a laterally recessed portion forming shoulders thereon, one shoulder at-one position of reciprocation of the pin disposed to engage tha-t arm of the bellcrank lever adjacent to the plunger thereby preventing swinging -of the lever,fsaid shoulder'adapted also in such position to be disposed underneath the beveled end surface'of the 'plunger to be engaged thereby to reciprocate the pin upon initial movemen-t of depression of the plunger thereby releasing the bellcrank lever.

EDWARD I. S'IULPIN. WALTER R. HAJDYLA.

REFERENCES CITED The following references are of record in the le Aof this patent:

UNITED STATES PATENTS Number Name Date 224,040 AProuty 2---.1 -.Feb. 3, 1880 541,454 Sweigart et al. June 18, 1895 

